Psychophysiological Indicators of Multisensory Processing in Autism Spectrum Disorder and Typical Development: A Pupillometry Study

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social communication and interactions (APA, 2013). Pupillary responses are a reliable indicator of cognitive operations including preference, mental load, and emotional arousal. The current study utilized pupillary responses to dynamic, audio-visual stimuli to infer cognitive processes involved in perception of social and non-social stimuli, as well as to temporally manipulated (i.e., asynchronous auditory and visual presentations) stimuli. The current study had four main research objectives: 1) to characterize pupillary responses to social and non-social information in ASD and typical development (TD), 2) to characterize responses to asynchronous and synchronous audio-visual stimuli in ASD and TD, 3) to determine whether pupillary responses can accurately predict membership to the ASD or TD group, and 4) to understand the relationship between pupillary responses and measures of ASD symptoms and social factors. Chronological and mental age-matched participants included 39 children with ASD and 32 typically developing children. Pupillary responses to social (Social-Linguistic, Social Non-Linguistic, and Social-Emotional) and non-social (Non-Social, Non-Linguistic) conditions were captured and recorded using an eye-tracker. Results yielded several key findings indicating differences between groups: 1) individuals with ASD demonstrated an attenuated pupillary response to social information, but not to non-social information, 2) in ASD, a reduction in pupillary response to social information was associated with greater impairments in social abilities and sensory processing as rated by caregivers, and 3) pupillary responses to social information was used to reliably predict group membership for children with ASD. Finally, this study did not observe between group differences in temporal processing, rather, both groups showed greater pupillary response to audio-leading asynchronous conditions, except for social-emotional conditions in which there was a significantly greater response to synchronous presentations. Results are discussed within the context of the engagement/arousal hypothesis of pupil dilation and the social motivation theory of ASD. Results are interpreted as evidence that reduced orienting to and under-engagement with social stimuli are implicated in the social impairments observed in ASD. This study demonstrates the usefulness and feasibility of pupillary response as a possible identification tool of the atypical social processing observed in ASD

Automatization and Retention of Literacy Skills in Adult Learners

Findings from recent efficacy studies comparing literacy program types suggest that struggling adult readers often make limited to moderate gains across varied types of literacy interventions, with no specific approach consistently surpassing others to date. An alternative to comparing program types is to investigate whether there are specific characteristics or skills that vary by individual that can predict higher gains and skill retention across program type. Using an experimental, prospective, longitudinal design, the present study examined the role of automatization (over-learning) of component skills involved in reading during participation in general literacy programs. On average, participants in the study gained the equivalent of one full reading grade-level after participation in programs for six months. The degree of automatization of reading skills was found to be the strongest predictor of gains made during programs; a measure of automatization was also the strongest predictor of subsequent retention of skills, months later at follow-up testing. Implications for adult literacy practitioners and directions for future research related to skill retention are discussed

The impact of multisensory integration deficits on speech perception in children with autism spectrum disorders.

Speech perception is an inherently multisensory process. When having a face-to-face conversation, a listener not only hears what a speaker is saying, but also sees the articulatory gestures that accompany those sounds. Speech signals in visual and auditory modalities provide complementary information to the listener (Kavanagh and Mattingly, 1974), and when both are perceived in unison, behavioral gains in in speech perception are observed (Sumby and Pollack, 1954). Notably, this benefit is accentuated when speech is perceived in a noisy environment (Sumby and Pollack, 1954). To achieve a behavioral gain from multisensory processing of speech, however, the auditory and visual signals must be perceptually bound into a single, unified percept. The most commonly cited effect that demonstrates perceptual binding in audiovisual speech perception is the McGurk effect (McGurk and MacDonald, 1976), where a listener hears a speaker utter the syllable “ba,” and sees the speaker utter the syllable “ga.” When these two speech signals are perceptually bound, the listener perceives the speaker as having said “da” or “tha,” syllables that are not contained in either of the unisensory signals, resulting in a perceptual binding, or integration, of the speech signals (Calvert and Thesen, 2004)

Conjunctive Visual Processing Appears Abnormal in Autism

Face processing in autism spectrum disorder (ASD) is thought to be atypical, but it is unclear whether differences in visual conjunctive processing are specific to faces. To address this, we adapted a previously established eye-tracking paradigm which modulates the need for conjunctive processing by varying the degree of feature ambiguity in faces and objects. Typically-developed (TD) participants showed a canonical pattern of conjunctive processing: High-ambiguity objects were processed more conjunctively than low-ambiguity objects, and faces were processed in an equally conjunctive manner regardless of ambiguity level. In contrast, autistic individuals did not show differences in conjunctive processing based on stimulus category, providing evidence that atypical visual conjunctive processing in ASD is the result of a domain general lack of perceptual specialization

La caractérisation des productions vocales d'enfants francophones euphoniques de 5 ans

L’objet de ce mémoire est la caractérisation des paramètres vocaux objectifs de la voix d’enfants francophones euphoniques âgés de 5 ans. Ce projet découle de la constatation, qu’à l’heure actuelle, dans la liste limitative des tests proposés par l’INAMI pour l’évaluation vocale de l’enfant, seules les normes pour la fréquence fondamentale sont disponibles. Celles-ci ont été réalisées auprès d’enfants néerlandophones âgés de 6 à 11 ans (De Bodt, 1997). Notre recherche s’inscrit dans la lignée du travail effectué par De Bodt. L’introduction théorique réalise l’état de l’art relatif à la caractérisation vocale des enfants. Le manque actuel d’études portant sur une population d’enfants francophones âgés de 5 ans est mis en exergue. Par ailleurs, les intérêts que peuvent revêtir ce genre de données sont soulignés. La partie expérimentale décrit le recueil et l’analyse des échantillons vocaux de 53 enfants de 5 ans scolarisés en 3ème maternelle. Chez chaque enfant, les tâches suivantes sont enregistrées : une production des voyelles [a :], [i :] et [u :], des sirènes ascendantes et descendantes, des crescendos et decrescendos et une histoire séquentielle. La méthodologie a été pensée afin d’adapter le bilan vocal à de jeunes enfants : les tâches sont intégrées au sein d’une histoire attrayante, des consignes métaphoriques et des supports visuels sont proposés. Trois objectifs sont poursuivis dans le cadre de ce mémoire. Premièrement, les valeurs de référence de dix paramètres vocaux sont obtenues à partir de l’analyse des voyelles : la fréquence fondamentale, le Jitter local, le Shimmer local, le NHR, la fréquence minimale, la fréquence maximale, l’étendue fréquentielle, l’intensité minimale, l’intensité maximale et la dynamique d’intensité. Deuxièmement, des différences selon le genre sont recherchées. Une seule différence statistiquement significative est trouvée entre la voix des filles et celle des garçons (pour le NHR de la voyelle [a :]). Troisièmement, un profil vocal récapitulatif est créé à l’intention des logopèdes cliniciens. Ce mémoire se veut le premier d’une série s’intéressant à ce vaste sujet encore peu investigué à ce jour. D’autres recherches pourront le compléter, notamment en poursuivant les analyses de la base de données récoltée.Master [120] en logopédie, Université catholique de Louvain, 201

Caractérisation de la voix d’enfants francophones euphoniques âgés de 5 ans

Cette recherche découle du manque actuel de normes acoustiques pour la voix d’enfants francophones. Méthode: Chez 53 enfants de 5 ans (26 filles ; 27 garçons), des analyses acoustiques ont été réalisées sur les voyelles soutenues [a], [i] et [u], sur des sirènes ascendantes et descendantes, et sur des crescendos et decrescendos. Les objectifs étaient 1) d’établir des valeurs de référence pour les paramètres acoustiques F0, jitter, shimmer, rapport bruit/harmoniques (NHR), fréquence minimale, fréquence maximale, intensité minimale et intensité maximale, et 2) de rechercher d’éventuelles différences selon le genre. Résultats: Seul le NHR diffère statistiquement selon le genre sur la voyelle [a]. Pour tous les autres paramètres analysés, l’absence de différence entre les filles et les garçons nous amène à proposer des normes conjointes qui aideront au diagnostic des troubles de la voix chez les enfants de 5 ans

Caractéristiques vocales d'enfants de 5 ans : Proposition de normes pour une population francophone

Purpose: Previous research proposed normative data on gender- and age-specific voice acoustics for adults. Such reference values are lacking for children, particularly under the age of 6. This study was intended (1) to collect reliable normative data for the acoustic parameters of 5-year-old children’s voices, and (2) to investigate potential gender-specific differences. Study: Prospective and cross-sectional. Methods: Acoustic analyses were done on the voices of 53 normophonic children (26 girls; 27 boys) aged 5;0 to 5;11 years, using Praat software. The fundamental frequency, local jitter, local shimmer, and noise-to-harmonics ratio (NHR) were measured on the sustained vowels [a], [i], and [u]. The highest frequency, lowest frequency, and frequency range were measured using ascending and descending glissandi on the vowel [a]. Results: For the three sustained vowels, the mean fundamental frequency ranged from 255 Hz to 277 Hz, mean jitter ranged from 0.394% to 0.591%, mean shimmer ranged from 2.571% to 5.824%, and mean NHR ranged from 0.009 to 0.034. The frequency range was from 190 Hz to 750 Hz, which corresponds to 23.7 semitones. No gender difference was found, except for NHR on the vowel [a]. Conclusions: The lack of gender differences – other than for NHR on the vowel [a] – led us to propose mixed norms for 5-year-old boys and girls combined. Implications: These normative data will allow clinicians to compare children’s voice assessments to specific references in order to enhance diagnostic accuracy and measure therapy outcomes